MAG58

1 fast Z, The timing system here is going to be complicated as expected, however it runs a timing chain of the same width between the rows and pitch as the L chain even though the tooth number is different, as two L series timing gears atop that head would make reasonable chain angles and follwers basically unfeasable. I plan on going soon to get the M104 timing sprocket to see how close it is to the L series crank snout journal. I know for sure the bottom timing cover will be modified by using an external water pump along with the aforementioned planned re-jacket. This will allow me to use a wider (space between the chains) tensioner and use less radical angles at the top end of the head. And I knew the 7M head doesn't flow that great, especially when you put a non-crossflow Z head next to it. I do however know that these engines have been and are raced in germany to great success. AMG, Barabus, and Schrick do or have at one time made cams for this car, along with springs, although the stock springs can be spun to 8500 without much problem. The lifters are hydraulic as pictured and I checked, are produced by the same mfg as the Audi 20V motor and those lifters can be seen in high rpm (8500+) race motors in europe and here using these lifters, though there are a few companies that are making a solid lifter conversion for these should you feel that you absolutely have to run SLA's. As far as flow goes, I know looks can be deceiving, but this casting is used in the German touring car series and is VERY competitive against 400hp NA BMW S motors. I cant yet provide with confidence the exact details on this motor. Benzworld along with a few german sites (first time i've ever used my high school and college german classes, take that education system!) have a wealth of information on these heads. Hope this helps, don't mean to step on anyone's toes. Bob

I've got a few more pics for you guys to see what this looks like before the block goes off to get bored and milled for the bigger head bolts... Here's what it looks like with the two respective front covers in place : And this is what the old, blown HG looks like sitting atop the L28 block [/img] Also of note, I just measured the F54/P79 combo in my Z currently, and the new head with the valve cover is just over an inch shorter on the short side of the head and slightly taller (maybe 1/4'') on the tall side of the head, so it should fit with no problem in the Z! Note this is was measured from the flange at the oil pan to the top of the valve covers at the center of each. Let me know what you think! Bob

You know if you're really feeling devoted you could throw an SR20VE head on it and make monster power I've heard they flow some seriously good numbers.

While I was looking at the merc engine, I will say this, It's front sump, and you'd have to cut the cross member or the firewall since it has a chain drive oil pump that sits below the front of the engine. It's actually similar to the BMW V12 design that a member here has documented switching to dry sump to rectify the situation. Though it's a stout engine, since it has that cool symbol, parts are pricey and factory non-auto cars are rare. fwiw, I just looked up the price of a factory new piston (just one) and it was 374 bucks I'm just trying to find a viable head option for the L series. If I was going to do an entire engine swap there are hundreds of Cheaper, faster, simpler, and probably more efficient options out there. Bob

That thing has more plastic in it than a Saturn! That said I too have seen a similar kit, so I'd say there's a good shot it's real.

FYI this is the M110 that Mack said would NOT fit, which has been a rumor since way before I was born... And this is a Picture of the M104 engine in bay, which is the head that I have. Note, the front of this engine has a dizzy on the exhaust camshaft, this is a 3.0-24 engine. My M104 3.2 head does not have this as it went to a DIS setup when they switched out the mech. Injection for the Bosch Electronic.

1 Fast Z, I PM'd Mack, Hopefully I will get some information soon, though searching through his posts, I found that the Cylinder head he was looking at was the older M110 engine that was out in the mid-80's. This was a 2 valve head and the M104 was a radical re-design with a fitting bore spacing and head bolt arrangement. The M104 was a re-design of the M103 head, which was an SOHC head. The motor can be found on W-124 and W-202 sedan's and coupes between 1990 (3.0-24 designation) and 1991-1997 (2.8 & 3.2 displacement) starting with the old Bosch mechanical injection Merc was so known for swapping to the electronic injected examples which is the head I have. As far as head flow, I don't have numbers, but just comparing exhaust between this motor and an RB, i have no doubt that the exhaust on this head will out flow a 26 head lift for lift with stock castings.

The timing Gears are incredibly close, though the L's crank gear is 20 teeth while the M104's is 36. I'm gonna go back soon an get the crankshaft sprocket and see how close that its, along with the tensioner since it is designed VERY similarly to the way the L series tensioner works. The front cover I think I can salvage, along with the Variable Valve electric over hydraulic system it uses for the intake cam . The front cover doesn't bolt to the bottom cam drive cover like the L series does, so some simple machining, countersunk screws and an adapter plate should work. This will hopefully give me a standard timing chain setup without the bothersome counter shaft or jack shaft arrangement. Thanks for all your comments and if anyone has any ideas on how to do anything differently than what I'm proposing, by all means speak up! I'm looking for all the input I can get. Bob

check out cheftrd's RB build stickey at the top of this forum. He's going to roughly the same application and power level and is pretty much going step by step on what he's doing to get his 26 that way.

Savage, I think what he's asking is if the AFR for a high comp motor should stay about the same as for a turbo motor, and the answer is every motor is different, but way richer than the stock curves would definitely be best and help knock, especially in hot Mexican summers so 11.0 would probably be a pretty good place to start and tune to.

It's really up to whoever owns the car, but as far as I'm concerned it's just another thing I'll eventually have to fix when it breaks. I've got a factory sun roof on my 720 pickup and to be honest, I just think it makes the car that much hotter in the summer. As for airflow, my 71 is almost black (charcoal metallic) and provided I'm not sitting still at an intersection, it cools off just fine with the windows down in a Southern Indiana August which stays pretty humid and can clip 100 a couple of days a week.

Finally an in on how to rectify this long lasting debate with women... "It's for the kids"

Time for more pics i've taken after I finished for the day with a customer car... Mike, The head is a little taller overall with the valve covers than the L series. The M104 engine actually lays at an angle as well and the side closer to the top of the engine bay (the intake side) is substantially taller. If anything the Hood Mount would have to be notched to fit the head. That said, since there have been questions about bore space I dug up some old L28 Head bolts and bolted the head up. I had to remove the alignment studs on the block, but the head bolted right on up using the longer 5 head bolts. I flipped the motor over and took these pics... Here's what number 3 cylinder looks like from the bottom : And here's cylinder 4 as viewed from the same prospective... Onto Oiling, The M104 uses HLA's which are very similar to the 1.8T 20V buckets if you've ever seen the Audi engine. They are fed by the bottom set of oil galleries (see below) and allows the valve to rotate. It feels as if the portion that engages the valve is actually on a thrust bearing, as it spins very freely on the 10 of the 24 I checked. This is a shot of the back side of the cylinder head, The 4 small holes directly below the cam seals (two on each side) are the oil galleries for the cams and lifters. Since the entire head is fed off of two pressure holes that sit right next to the back two head bolts, I plan on plugging them and running hard lines to these to allow me to plumb them to the L's main oil gallery. Firewall clearance shouldn't be an issue, as the head is a little shorter than the L head. Finally the head bolts, as I said earlier, using the longer head bolts, which this is a picture of, the head does bolt up to the L block without modifications to the bolt holes in either the head or the block. The threads on the the M bolt don't actually thread that far into the block, as the L series long head bolt is within .020" from the shoulder to the tip of the threads.

yep

Given all the other problems, using a remote mount filter is the least of my issues ...

1. Perhaps. It'll run hotter and have more resistance than a larger cable of the same material. 2. yes.

Completely assembling a transmission only to realize you forgot the baulk ring on 1st Gear? ...been there.

Update: I went to Indy yesterday to see what's at the local Pull-a-Part, and found sitting there an M104 Merc Cylinder head. So for 40 bucks, I pulled it and nabbed all the goodies and brought them home to see if it fit. It did ... The bore spacing is DEAD ON and the head bolts are very close, in the small thousandths , which is doable. That said, I took some pics of the head vs a stripped P79 I had just sitting around and threw it on the block to see what it would look like. Right now it's just sitting there, because I couldn't find a stock set of Z head bolts. It would actually bolt up using them, but I'd like to bore for the bigger Merc head bolts since they're massive. Here's the comparison of the Exhaust sides... The M104 has nice bigt exhaust ports. On the intake, it looks like a big version of the L series intake port. Here's what the CC's look like... The stock M104 has 88.5 Bores for the 2.8 and 89's for the 3.2 so the valves are good sized. On the block it just looks even better, this is how the front cam drive lines up... And the Exhaust comes out on the low side of the engine, so with the factory lean over on the L28, a turbo should tuck up nicely on the underside with all that room on the driver's side of the engine bay for intake. That said, It's not going to be a cake walk by any means, I'm going to have to run an external oil feed and return and I'm going to have to close up the water jackets between the head and block to make them fit. For water return, it seems like pulling the 5 freeze plugs and tapping them for water will be the intelligent thing to do, coupled with the water exit that comes out between the two cam gears...

It would make sense, the AFM has to be changed to deal with the 200cc's less displacement the ECU will be controlling and if he put all the other ZX bits on it, it's really just controlling the same motor. But you shouldn't need an AFM for megasquirt?

I love the GTi-R motor and if you put it in a Z, it'd make for a killer little car. Solid lifters, ITB'S factory, bigger bearings, stronger block, it's a great little motor. Though wouldn't you have to run COP since the dizzy pops out the back of one of the cams? The 54C head flows pretty well too, IIRC. There's quite a few people around here that have the Sr swap before and a wealth of knowledge here. Just search around and you should find anything you need. Bob

Take mom with you.

Only when you treat them like piston engines. Rotaries are a special breed, but if treated correctly, a 1000+ 4 rotor should last just as long in race use as, say, a 1000hp 2-3l piston engine. When Mazda raced their 787B, they kept the shift point at 7500 IIRC, because they thought that a 9k shift point would wear out the motor. (by 9k the motor was making 300hp more than it was at 7k) But when they tore it down after the LeMans, the motor had yet to polish off the machine marks on the irons. They can be stout.

A stick of butter? I think a ride in an F15 would be nice... Boom the White House

You'll probably lose a good bit more than that individual cylinder's share of the load. In modern cars, they intake and exhaust is designed to function properly with all cylinders running. The engine will also have to overcome the drag that this parasitic cylinder will now create. That is instead of adding power, the other 3-5 cylinders have to the wasted energy of turning those cam lobes and the friction of the piston in the cylinder and the piston on the crank case. These and an engine running really out of balance would probably mean that 160hp would be closer to 100hp with one hole out.

Agreed, And I'm not sure if I'm a fan of the 'fangs' in the front fascia either... But it's still a gorgeous car.